How to connect/control laser add-on

Hey folks, been gone far too long and am currently doing some upgrades to the ol’ PRT96. New 2.2Kw spindle sand VFD. New dust boot, Dual Vee rail caps on X&Y axis.
But I’ve been looking at adding an 8watt laser to the setup. Before I take the plunge and buy one designed to add on to a Z axis, I want to be confident I being able to control to firing of the laser. The PMW would be externally controlled.
Move searched the forum (albeit, briefly) and I can’t seem to find a “How To” on adding a laser.
Anyone have some insight?
Thanks in advance.

http://www.talkshopbot.com/forum/sho...ht=Jtech+laser

Search for "jtech laser"...

Thank you Brady! I did read a few of those posts prior to starting this thread. I guess I’m looking for info on electric adaptation and suggestions on post processor.
I am more intrigued now at this.

You just need to tell the laser to turn on & turn off at the right times. See attached PP that turns output 5 on and off. Use it in conjunction with the laser trigger wires in Output #5 & Gnd on the control board. Some use the relay board (available from SB) if the 5v TTL signals from the control board don't have enough oomph to trigger the laser. Wiring on newer PRS shown in pic below. If you have another model SB, the connections are the SAME. Output 5 and Ground (Gnd).

Attachment 32689

Just for understanding/simplification - the only thing the Output is really doing is changing from an open switch to a closed switch when triggered by the SO,5,1 command in your SBP part file. It opens/goes off when given the SO,5,0 command (Set Output 5 , 0 [OFF]) That's it. Think of it as a digital toggle switch. If yours doesn't function that way, make sure Output 5 is configured correctly in SB3 by running the VN command. Scroll down to the outputs and make sure Output Switch #5 Mode is set to "0".

You can look at how JTech did the wiring on a ShopBot here

See attached post processor (unzip it) that *should* work with the same wiring scheme. I take no responsibility for it working or not...use at your own risk and do your own proofreading/testing/checking. However, others using this PP with the JTech and SB relay board have told me it works perfectly. It should work the same without the relay board. Obviously...extract the ZIP to your PostP folder...

Good luck...post a follow up and pics when you get it working.

I had been thinking of adding a laser to my SB but after seeing several purpose built lasers in action, I decided it wouldn't be worth the effort to modify my SB. For one, the fumes are going to be a real problem. Lasers generate a lot of smoke and unless you have some way of dealing with that, you're going to find it intolerable. If you have any sort of smoke/fire detection in your shop, it's going to go insane. Brady already went into the issue of low power.

The SB is total overkill for a laser. It might be fun as a test or hobby thing but I doubt there can be any production value in adding a laser module to your SB. Just my two cents.

Hey Brady, always a wealth of knowledge and experience. You are such a fantastic resource for a hobbyist as myself. I plan on studying this information over the next few days so as I can now/learn the ideals. I wish I could thank you in person, Maybe one day.....

Hi Coryatjohn. I am taking ALL aspects of this endeavor into consideration. I have used a couple of commercial laser engravers before (on construction sites of all places). I would love to by a dedicated machine for this whole process, but as this is currently a hobby now, and real estate in the shop at a premium, I am looking at this option with caution. I am the type that needs to know the whole picture and consider all aspects prior to attempting a change.

You're welcome.

Have a look at OPT Lasers too... particularly how they mount it with magnets and contacts for easy on and off of the head. Even just mounting it with magnets and a molex connector would let you put it on or take it off in seconds...

These low power lasers don't generate a lot of smoke...but it's a good idea to ventilate the shop.

Protect your eyes 1000% of the time. The danger is invisible and you only get two of them....:rolleyes:

Also good advice. Thank you again.

These little add on lasers have come such a long way and are so inexpensive in comparison to where it was I'm thinking of hanging one off my desktop!
Fun stuff only. (But I'll probably think about it for a while yet-Still have some infrastructure stuff to finish up on my shop interrupted for a while by unforeseen circumstances.)